Re: [PATCH] bus: mhi: Add inbound buffers allocation flag

[Hemant Kumar <hemantk@codeaurora.org>]

On 1/8/21 7:30 AM, Manivannan Sadhasivam wrote:
> On Fri, Jan 08, 2021 at 03:01:59PM +0100, Loic Poulain wrote:
>> Hi Mani,
>>
>> On Fri, 8 Jan 2021 at 14:44, Manivannan Sadhasivam <
>> manivannan.sadhasivam@linaro.org> wrote:
>>
>>> On Wed, Jan 06, 2021 at 02:43:43PM +0100, Loic Poulain wrote:
>>>> Currently, the MHI controller driver defines which channels should
>>>> have their inbound buffers allocated and queued. But ideally, this is
>>>> something that should be decided by the MHI device driver instead,
>>>
>>> We call them, "MHI client drivers"
>>>
>>
>> I'll fix that.
>>
>>
>>>> which actually deals with that buffers.
>>>>
>>>> Add a flag parameter to mhi_prepare_for_transfer allowing to specify
>>>> if buffers have to be allocated and queued by the MHI stack.
>>>>
>>>> Keep auto_queue flag for now, but should be removed at some point.
>>>>
>>>> Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
>>>> ---
>>>>   drivers/bus/mhi/core/internal.h |  2 +-
>>>>   drivers/bus/mhi/core/main.c     | 11 ++++++++---
>>>>   drivers/net/mhi_net.c           |  2 +-
>>>>   include/linux/mhi.h             | 12 +++++++++++-
>>>>   net/qrtr/mhi.c                  |  2 +-
>>>>   5 files changed, 22 insertions(+), 7 deletions(-)
>>>>
>>>
>>> [...]
>>>
>>>> diff --git a/drivers/net/mhi_net.c b/drivers/net/mhi_net.c
>>>> index fa41d8c..b7f7f2e 100644
>>>> --- a/drivers/net/mhi_net.c
>>>> +++ b/drivers/net/mhi_net.c
>>>> @@ -265,7 +265,7 @@ static int mhi_net_probe(struct mhi_device *mhi_dev,
>>>>        u64_stats_init(&mhi_netdev->stats.tx_syncp);
>>>>
>>>>        /* Start MHI channels */
>>>> -     err = mhi_prepare_for_transfer(mhi_dev);
>>>> +     err = mhi_prepare_for_transfer(mhi_dev, 0);
>>>
>>> Eventhough I'd like Hemant to comment on this patch, AFAIU this looks to
>>> me a controller dependent behaviour. The controller should have the
>>> information whether a particular channel can auto queue or not then the
>>> client driver can be agnostic.

I am fine with his change, and agree that MHI client driver should be 
able to make the decision.
Having said that, can we merge this on top of UCI :).
[..]

Thanks,
Hemant
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